1. Technical Field
Example embodiments of the present invention relate in general to the field of device-to-device (D2D) group communication and more specifically to a D2D group communication method and a device using the same.
2. Related Art
Recently, the number of times of overload occurring in a mobile communication network has increased with an increase in the use of applications that transmit/receive a large volume of data using a smart phone on the move. Thus, the occurrence of a network failure and the degradation of quality of service (QoS) are seriously problematic.
As a solution for these problems, technology for providing D2D communication with an adjacent device located in the same cell or a peripheral cell within a radius of 1 to 2 km in a mobile communication system is being considered.
D2D communication is a communication scheme for performing direct data transmission/reception between two adjacent devices without involving a base station. That is, D2D communication technology is technology in which data is directly exchanged between devices through a D2D wireless link without involving the base station after the D2D wireless link is set up through a mobile communication radio interface using a mobile communication frequency band between adjacent devices.
This D2D communication technology has various advantages. Existing technologies such as wireless fidelity (Wi-Fi) direct, Bluetooth, and Zigbee can support only communication between devices within several hundreds of meters, but the D2D communication technology enables direct communication between devices located within a radius of 1 to 2 km to be performed based on medium/long distance transmission capability provided by a mobile communication radio interface.
Also, it is possible to reduce a load on a network because communication between adjacent devices does not involve the network. In addition, only low-rate data transmission is possible when adjacent devices located in a cell boundary region communicate with each other via a base station. However, it is possible to provide users with a service of further improved performance because high-rate data transmission is possible in a better signal environment when adjacent devices directly communicate with each other.
Additionally, although each device should maintain high transmission power that reaches the base station when the adjacent devices located in the cell boundary region perform communication via the base station, a lifespan of a battery can be prolonged because transmission power is significantly reduced when direct communication between the devices is performed.
This D2D communication is not limited to only communication between two devices, and group communication to which three or more devices join is possible. However, particulars for supporting group communication in D2D communication have not been proposed up to now.